Installing CPA

In this lab exercise, we'll be installing CPA using Kustomize manifests, the main part of which is the Deployment resource below:

~/environment/eks-workshop/modules/autoscaling/workloads/cpa/deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: dns-autoscaler
  namespace: other
  labels:
    k8s-app: dns-autoscaler
    kubernetes.io/cluster-service: "true"
spec:
  selector:
    matchLabels:
      k8s-app: dns-autoscaler
  template:
    metadata:
      labels:
        k8s-app: dns-autoscaler
    spec:
      securityContext:
        seccompProfile:
          type: RuntimeDefault
        supplementalGroups: [ 65534 ]
        fsGroup: 65534
      nodeSelector:
        kubernetes.io/os: linux
      containers:
      - name: autoscaler
        image: registry.k8s.io/cpa/cluster-proportional-autoscaler:1.8.5
        resources:
            requests:
                cpu: "20m"
                memory: "10Mi"
        command:
          - /cluster-proportional-autoscaler
          - --namespace=kube-system
          - --configmap=dns-autoscaler
          - --target=Deployment/coredns
          - --default-params={"linear":{"nodesPerReplica":2,"min":2,"max":6,"preventSinglePointFailure":true,"includeUnschedulableNodes":true}}
          - --logtostderr=true
          - --v=2
      tolerations:
      - key: "CriticalAddonsOnly"
        operator: "Exists"
      serviceAccountName: dns-autoscaler

Let's apply this to our cluster:

~$kubectl apply -k ~/environment/eks-workshop/modules/autoscaling/workloads/cpa

This will create a Deployment in the kube-system namespace which we can inspect:

~$kubectl get deployment dns-autoscaler -n other

NAME             READY   UP-TO-DATE   AVAILABLE   AGE

dns-autoscaler   1/1     1            1           10s

After CPA starts up it will automatically create a ConfigMap we can modify to adjust its configuration:

~$kubectl describe configmap dns-autoscaler -n kube-system

Name:         dns-autoscaler

Namespace:    other

Labels:       <none>

Annotations:  <none>

Data

====

linear:

----

{'coresPerReplica':2,'includeUnschedulableNodes':true,'nodesPerReplica':1,'preventSinglePointFailure':true,'min':1,'max':4}

Events:  <none>